Extensible height-adjustable swivel arm for supporting a display or the like

Abstract

A swivel arm structure suitable for supporting a video display apparatus or the like and for positioning such apparatus with substantial discretion and ease. A first, horizontally movable arm is pivotally attached to a fixedly mounted base, which movable arm can be articulated at multiple movement interrelated joints within the horizontal plane. A vertically translating parallelogram type linkage is attached at one end to the horizontally articulatable arm and at the other end supports the apparatus. In one form one linkage member is situated within the tubelike structure of the other linkage member. The swivel arm can be freely moved, without angle induced binding of hinges, to position the apparatus.

I claim: 
     
       1. A swivel arm structure, comprising: a base for fixedly supporting the structure;   an articulated member of three elements, the first element rotatable at its first end about the vertical axis of the base, a second element attached at its first end to a second end of the first element and rotatable about the vertical axis at such attachment, and a third element attached at its first end to a second end of the second element and rotatable about the vertical axis at such attachment;   a parallel lever arrangement translatable in the vertical plane, attached at one end to the second end of the third element; and   an apparatus support attached to the second, oppositely disposed end of the parallel lever arrangement.   
     
     
       2. The structure recited in claim 1, wherein the parallel lever arrangement is comprised of a first tubelike lever and a second lever arranged therein. 
     
     
       3. The structure recited in claim 2, further including a spring element arranged within the first lever connected to act on the articulated member and the apparatus support. 
     
     
       4. The structure recited in claim 1, wherein the second element includes a gear arrangement for relating horizontal plane movement between the first and third elements. 
     
     
       5. The structure recited in claim 2, wherein the second element includes a gear arrangement for relating horizontal plane movement between the first and third elements. 
     
     
       6. The structure recited in claim 4, wherein the gear arrangement includes a pair of meshing gears in the second element which further individually mesh gear teeth on the first and third elements. 
     
     
       7. The structure recited in claim 5, wherein the gear arrangement includes a pair of meshing gears in the second element which further individually mesh gear teeth on the first and third elements.